Nightly News | August 20, 2011
>>> those flash floods in pittsburgh we told you about just before the break are just the latest weather disaster in an especially deadly year, from tornadoes to wildfires, drought and extreme heat. it's been a nonstop cycle of extreme weather from coast to coast . our report tonight from nbc's mark potter .
>> reporter: from coast to coast , it's been a disastrous year weatherwise in the u.s. the worst was in joplin, missouri, which was demolished by a huge tornado in may with 160 people killed, 8,000 homes and businesses destroyed. during a rash of tornadoes this spring, many other cities were hit.
>> in any year we typically see weather extremes. this year, however, we've seen the extreme of the extremes.
>> reporter: in the southwest, extreme heat brought wildfires, drought, crop and livestock losses. flooding caused widespread damage in the upper midwest and mississippi valley . and early in the year, tons of heavy snow ground parts of the midwest to a halt. and now we're in hurricane season . so far this year, only a weak tropical storm has hit the united states . but we are now entering the statistical height of hurricane season . the weather this year has killed more than 600 people nationwide. and already nine separate weather events have each caused more than $1 billion in damage, tying a record set during all of 2008 . total losses to homes, businesses and agriculture, $35 billion. forecasters blame the combination of an unusually active global weather pattern and population growth in vulnerable areas.
>> even weather has the potential to affect more harm on society because there are more people and there are more things in weather 's way.
>> reporter: to make america safer, the national weather service is launching a project called " weather ready nation." in six cities over the next month, it will test a new severe weather warning system and better emergency response procedures.
>> we had over 540 people lose their lives in tornadoes alone this year. i know we can bring that number down.
>> reporter: an effort to save lives in a year when the weather just will not let up. mark potter , nbc news, miami.